[QA] (A) While the campaign, young volunteers helped (B) build bridges, (C) roads and houses for some of Viet Nam’s most (D) disadvantaged families.

Question:

(A) While the campaign, young volunteers helped (B) build bridges, (C) roads and houses for some of Viet Nam’s most (D) disadvantaged families.

• A.
  A
• B.
  B
• C.
  C
• D.
  D